Combination governor and ignition system for internal-combustion engines



March 20, 1951 SMITLEY COMBINATION G0 ERNOR AND IGNITION SYSTEM FORINTERNAL-COMBUSTION ENGINES Filed Sept. 23. 1948 INVNTOR.

BY MM Patented Mar. 20, 1951 COMBINATION GOVERNOR AND IGNITION.

SYSTEM FOR INTERNAL-COMBUSTION ENGINES Marion L. Smitley, Detroit,Mich., assignor to George M. Holley and Earl Holley ApplicationSeptember 23, 1948, Serial No. 50,718

1 Claim. 1

The object of this invention istocontrol the spark advance when using asandwich type. governor on an automotive engine with a well knownpressure (suction) controlled ignition system. In a-sandv/ich governorthe governor throttle is mounted downstream of the main throttle-in ahousing-which is the sandwich between the inlet manifold and thecarburetor. When such a governor acts, the manual throttle being locatedupstream of the governor throttle and being wide open, there is a dangerthat the spark will not be correctly controlled for all conditions andthat the calibration established for the carburetor, without thesandwich governor, will be lost.

The figure shows diagrammatically the preferred formof my. invention.

In the figure air enters at l6 and flows through a venturi l2, past afuel nozzle |.4 fed from a float chamber, not shown. A restriction I3 islocated in the throat of the venturi l2 and is connected through a pipewith a chamber 22 which contains a spring 24 and a diaphragm 28 whichforms the moving wall of chamber 22 and 28 and is connected through arod 30 with a spark advance device 34. An increase in suction in chamber22 advances the spark in the well known manner without the use of theconventional centrifugal weights.

A passage 36 is connected to the restriction l8 and also through arestriction 38 to the mixture outlet at a point located just above thelip of the throttle 42 when the throttle 42 is in its idling position.This gives the desired retarded spark for idle and an immediate advancewhen the throttle is first opened away from idle.

A governor throttle 44 is connected to a lever which is connected to agovernor, not shown. A passage 50 is normally located above the governorthrottle when this throttle is in control and is connected to a chamber54. For reasons of economy and space the sandwich containing thethrottle 44 is made as thin as possible, otherwise passage 50 would belocated at a higher level.

A second moving wall or piston 56 is pushed to the left by a compressionspring 60 when pressure in passage equals pressure in passage 56, thatis, when the governor throttle is more than one-half way.

A restricted passage 64, in the piston 56, forms the connection betweenthe passages 36 and 14 with a passage 16, which passage is connected tothe mixture outlet downstream of the governor throttle 44. An annularport 12, in the piston 56,

communicates withpthe restriction 64 and also with a passage 14 when thepiston is drawn to the right by the suction in the passage 10 into theposition in which it is shown, which is. the position in which thegovernor is acting to control the speed of the engine by the throttle44, the throttle 42 being then wide open. Under these circumstances, theengine suction, acting through restriction 64, is strong enough tocreate a suction in chamber 22 to advance the spark in spite ofthe airleaks at restrictions I8 and 38.

At certain positions. of the throttle 44 the restriction 64 is cut offfrom passage 14 and an undesirably low suction will exist in chamber 54and not enough suction in chamber 22'. To avoid this a passage 5|. canbe usedin. place of or in conjunction with passage 50. Passage 5|islocated outside of the zone influenced by governor throttle 44.

If this device is sold as an accessory tov existing carburetors it isimpossible commercially to drill holes such as 5| and 14 in the flangeof a carburetor. In that event 14 is replaced with a tube and a T jointmade with pipe 20, and only passage could be used. Theoretically passage5| is superior to passage 50. Actually it would make little differenceas once the governor acts the throttle 44 closes to a position whichopens the passage 14 to the restriction 64 by admitting substantiallyatmospheric pressure to chamber 54.

Operation At low speeds when the governor throttle 44 is wide open andthe throttle 42 partly open, the suction in chamber 22 follows theincrease in suction below the throttle 42 through the driving range andadvances the spark by the suction transmitted through the restriction 3Bin the well known manner of operation for this type of ignition.

- During wide open operation of throttle 42 (throttle 44 being also wideopen) the suction in chamber 22 follows the speed and advances the sparkby reason of the depression in the venturi transmitted through therestriction l8 to the chamber 22 in the well known manner. The flowthrough restriction 38 then acts to slightly reduce Venturi suction.

During governor operation the throttle 44 closes and suction, to theright of piston 56, placesrestriction 64 in communication with passages|43620 and chamber 22 as shown in the drawing. Restriction 64 overcomesthe effect of both restrictions l8 and 38. Hence, the spark is advancedas the throttle 44 closes in response to governor action exactly as itwas advanced when the governor was not in action and throttle 42controlled the speed. The suction in chamber 22, as before, advances thespark.

When both throttles 42 and 44 are wide open the piston 56 again shutsoff all communication between passage 10, 64 and 12, which is nowsubstantially at atmospheric pressure, and passages 1436-30 and chamber22.

Hence, with this invention there is no interference with the wide opencontrol of the spark advance and the suction at [8 is only reduced, asbefore, by the small quantity of air bled through restriction 38 atpractically atmospheric pressure (at lowest engine speed). Hence, theoriginal calibration is satisfactory in spite of the governor. If airwere to be introduced also through restriction 64 then the calibrationof the ignition device for wide open operation would be quite in errorbefore the governor acted to check the speed. This would cause a seriousloss in torque.

The size of restriction 64 is selected so that the spark responds to thesuction in passage 70 exactly as the spark responds to the suction inmixture outlet 40 when the throttle 44 is open and throttle 42 controls.

- When the governor throttle as is wide open the throttle 42 controlsthe spark through the restriction 38 and again the restriction E l,being closed, does not interfere with the advance as then the pressurein passages 50 and it are equal so that the spring 60 prevails and againthe restriction 64 will not introduce any disturbing elements into theautomatic spark advance control.

What I claim is:

An internal combustion engine in combination, an air intake to saidengine, a venturi therein, a main air outlet passage from said venturi,a first throttle therein, a second throttle downstream therefrom adaptedto be connected to an automatic governor, an ignition timing device forsaid engine, first yieldable means for retarding the spark, vacuumoperated means for advancing the spark in said engine by overcoming saidfirst yieldable means comprising a suction chamber having a first movingwall connected to said timing device, a first restricted passageconnected to the throat of the venturi and to the chamber, a secondrestricted passage connected to the chamber and to the outlet passage onthe engine side of said first throttle when said first throttle is firstopened to operate the engine, a third restricted passage connected tothe vacuum operated means and to the engine side of said secondthrottle, a valve in said third passage, a second moving wall connectedto said valve, second yieldable means engaging with said wall to closesaid valve, a second chamber associated with said second moving wall andconnected to the main outlet passage on the atmospheric side of saidsecond throttle when said second throttle acts to control the speed, athird chamber on the other side of said second moving wall, a passageconnecting said third chamber to the outlet from said main outletpassage on the engine suction side of said second throttle, thedifference in pressure between second and third chambers associated withthe second moving wall opposing the second yieldable means so as to openthe restriction in said third passage when the second throttle acts togovern the speed of the engine so that the governor simultaneouslythrottles the flow of air through the venturi and advances the spark.

MARION L. SMI'ILEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,039,396 Darnell et al May 5,1936 2,128,363 Jennings, Jr. Aug. 30, 1938 2,200,043 Sarnes May 7, 19402,377,566 Mallory June 5, 1945

